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Queen Victoria was a fan of 3D technology long before James Cameron created Avatar.

She became a patron of the imaging technique that was all the rage in the mid 1800s after she saw it at the Great Exhibition at Crystal Palace in 1851.

Fast forward a century or two and 3D technology has become the latest buzz in big and small screen entertainment.

But not everyone's a fan. According to US film critic and Newsweek columnist, Roger Ebert, "3D is a waste of a perfectly good dimension".

"It adds nothing essential to the movie-going experience. For some, it is an annoying distraction. For others, it creates nausea and headaches.

"Its main aim is to sell more equipment to movie theatres. Many directors, editors, and cinematographers agree with me about the shortcomings of 3-D. So do many movie lovers — even executives who feel stampeded by another Hollywood infatuation with a technology that was already pointless when their grandfathers played with stereoscopes," he recently wrote.

What is 3D?

The term 3D covers a number of related, but different things. In pure terms, three dimensions or 3D refers to the way we perceive an object in space. The three dimensions are width, height and depth. A square has two dimensions (2D) but a cube has the added third dimension.

3D vision or stereoscopy is the ability to view something with two eyes to give a three-dimensional sense.

Stereo vision in humans relies on the two eyes being able to track with each other (binocular vision). Even if you cover one eye it will still track along with the eye that can see. A common exception to this is the vision defect knows as strabismus, where one eye is 'lazy' and does not track properly. People suffering this will not see true stereo vision.

While binocular vision is almost standard in the animal kingdom, not all animals see the way we do. For instance horses have eyes on the side of their head, and so mainly see two separate images, one from either side. They even have a blind area in front of their nose that extends out to around 1.5 metres.

The evolution of 3D imagery

Stereoscopy was invented a few centuries ago using pairs of drawings or paintings that were viewed side-by side to give the stereo effect.

Almost as soon as photography was invented in the first half of the 19th century it was used to produce stereo pairs of images. These images became a huge hit around World War 1.

It was popularised again in the 1930s by the invention of a 'toy' 3D viewer — an inexpensive stereoscope that has a pair of viewing lenses in the front like a pair of binoculars.

Millions of stereo viewers were manufactured and there were tens of thousands of mass-produced stereo cards on sale.

The images are taken using three different methods. One method uses a pair of cameras mounted side-by-side, taking simultaneous photos from slightly different positions (to mimic the distance between the human eyes). It's also possible to take two photos with the same camera, moving it sideways between shots. The third method uses an image combiner to project two separate images onto a single piece of film. Only the first and last methods could capture a moving scene.

Perhaps the first 'real' application of stereo photography was during World War II when reconnaissance planes on both sides took stereo images which were then analysed by intelligence officers. Using these stereoscopic pictures they were able to much more easily spot and identify objects that stood out from the ground, such as buildings, towers, bunkers, vehicles and even rockets.

Early 3D movies, which were first invented in the early 1900s, used the anaglyphic system. Stereo images filmed in black and white were superimposed on the film, but in different colours. Typically the left image was blue and the right image was red. When viewed through glasses that had red and blue coloured lenses each eye would only see the image meant for it. That is, the blue lens would show a blue image as light and a red image as dark.

Strangely enough the brain is able to cope with seeing two wildly different colours, and can make sense of the resulting stereo image. The main drawback was the inability to use colour photography. These films were usually shot using a pair of cameras, side by side. It was expected that the director would employ tricks such as throwing an object or thrusting a knife into the viewer's face.

It was later discovered that some colour could be introduced into the images, giving a pseudo-colour effect. Some movies have recently been released using this method. But again, most of the effect relies on the flexibility of the human brain.

Colour 3D films became possible through the introduction of spectacles using polarising filters in the 1950s.

One image is projected through a horizontally polarised filter and the other through a vertically polarised filter. If the image is projected onto a silver screen the polarisation is preserved and the viewer saw sees a colour 3D movie through a pair of glasses — one side polarised at 90 degrees to the other. When viewed without the glasses both eyes see both of the images so the picture became becomes quite blurred. Unfortunately if the viewer tilts their head the images will also bleed into the wrong eye, ruining the effect.

3D in 2010

Pandora's box: 3D movies such as Avatar are more popular than the 2D version of the same movie by 4:1
(Source: Christian Hartmann/Reuters)

Modern 3D movies such as Avatar use circular polarised lenses, which only pass light with a correct (clockwise or anticlockwise) polarisation. These glasses have the advantage that you can even tilt your head on the side and still get the 3D effect with no bleed-through.

The most recent advance in stereo imaging, used by 3D TV and some IMAX theatres, is to project the left and right images alternately, in very rapid succession. The viewer wears glasses with electronic shutters in them that synchronise with the screen. Thanks to the effect known as persistence of vision (which already allows film and video to work) the viewer sees a flicker-free stereo image. However, to obtain this smooth effect the screen must refresh more quickly than normal. The viewing glasses use LCD (liquid crystal display) lenses that are turned on and off by electronic pulses, usually powered by a battery in the glasses and controlled by an infra-red signal transmitted by the displaying system.

In the near-future, you will be able to watch 3D TV without glasses. This is known as autostereo. Some manufacturers have shown prototypes and even production models of autostereo TV sets but these have yet to reach the Australian marketplace.

What's not 3D?Not everything that is called 3D is actually true 3D. For example, most 3D TV sets have a pseudo 3D mode. This takes standard (2D) programs and by using some fancy computing tricks causes some parts of the picture to appear to be closer to the viewer. But this is NOT true 3D.

Some TV cartoon shows are produced in '3D' which can be a confusing misnomer. The images are still 2D but have added cues such as lighting, focus and shadows to give the characters a more lifelike look. These cartoons are usually computer generated.

Likewise many of the latest computer games are in 3D. Again, the image is still 2D but the environment has three dimensions and so gives a more lifelike appearance to the player.

A passing fad?

A holograph is projected above a mobile phone by a 3D projecter displayed in the Innovision booth at the Computex 2010 computer fair in Taipei.
(Source: Pichi Chuang/Reuters)

But is 3D just a passing fad as Ebert suggests?

3D is here to stay whether you like it or not, says Steve Quartly, whose Australian company Digipix produces 3D ads for TV and cinema.

"The figures tell the story. In general, cinema audiences are choosing to watch a 3D movie ... over the 2D version of the same movie by around 4:1. Even with the smaller 3D releases the ratio is about 3:1."

"If the 3D is done properly, it can add a whole new dimension to the movie. No one wants to be constantly 'poked' in the head with a yoyo, or continuously swooped on by pterodactyls."

Australian inventor Ross Stokel agrees we are primed to accept and want 3D technology, as long as it lives up to its claims.

"As we are a stereo-dependent species, the future of 3D media is assured and inevitable," he says.

Stokel, who has spent more than 25 years developing 3D capture and display systems, also believes that much can be done using existing technologies such as binocular head-mounted displays using extremely high resolution displays, virtually indistinguishable from reality.

3D technology is not only creating a revolution in entertainment but in applications such as medical imaging, remote manipulation of machines, weather event modelling and prediction and large scale modelling of geological deposits.

CSIRO geochemist Dr James Cleverley says geologists will increasingly need to build and use 3D lithological, mineralogical and geochemical models at all scales to ensure they are aware of every process that is happening to obtain a truly holistic view of a mineral system.

"A mineral system is much larger than a single ore deposit. An ore deposit might be a few hundred metres across but the mineral system could be five or six kilometres wide," he says. "If you understand the mineral system you will understand better the characteristics of the ore deposit and how it was formed, and your search for the mineral will be more efficient and effective," Cleverley says.

And who knows, one day we might be able to see computer-generated people and scenes on the holodeck, just like in Star Trek. Although the objects can't be touched, they appear just as if they're real, and can be viewed from any direction.

This is just wishful thinking at the moment, but rudimentary holography does exist, as demonstrated on credit cards, product stickers and even some bank notes around the world.

The principle technology involves illuminating the object or scene and capturing the light interference patterns generated. This can be reversed by exposing the image to another light source, thus creating some of the 3D properties of the original object or scene. The same effect can be created by computer and/or stored in a digital format.

How long until we see Holodeck quality? Ask the next time traveller who knocks on your door.

Hans :

ProCactus :

"As we are a stereo-dependent species, the future of 3D media is assured and inevitable," he says.

That quote in the above text should give people the realization that it is the pinnacle of Audio and video.

Just look at stereo audio. How much difference is it to mono?.The same can be said about video.Audio might come in 5.1 or 7.1 or 9.1 or even 28.1, It always comes back to two ears. With a bit of processing, Audio can be in true surround with just 2 speakers.I believe video is no different, Just a little harder. It also come with more specifications which makes it harder for people to understand what is what.

Once a permanent standard of 3D video storage comes in to play there will be a variety of ways to reproduce it. Just like in the Audio format.

Austra.Lianne :

22 Jun 2011 2:11:53pm

I can't watch 3D at all. It's always made me sick, and even when I tried to watch Avatar in 3D (after being told how much improved it was) it was no more than 20 minutes before I was in the loo losing my dinner!